Since their first publication, the four volumes of the Cambridge History of American Foreign Relations have served as the definitive source for the topic, from the colonial period to the Cold War. The first volume proposes that the British North American colonists' pre-existing desire for expansion, security, and prosperity is both the essence of American foreign relations and the root cause for the creation of the United States. The second describes the dynamics of United States foreign policy from 1865 to 1913, the era when the United States became one of the four great world powers and the world's greatest economic power. The third describes how the United States became a global power during the period from 1913 to 1945, from the inception of Woodrow Wilson's presidency to the end of the Second World War. The revised and expanded fourth volume explores the conditions in the international system at the end of World War II, the American determination to provide leadership, and the security dilemma each superpower posed for the other, while incorporating recent scholarship and revelations, and carrying the narrative into Barack Obama's administration.